Interesting subject! A while ago I mentioned in a posting that I had replaced the gas struts on my -71 Porsche 911T last summer. Yesterday I was disconnecting the battery and CLUNK, the hood hit me in the head! Not slam-bang, just a slow descent, but nevertheless irritating. My second thought was that there got to be a way to test these things. Obviously you are way ahead and it will be interesting to find out how your trial to test the gas pressure with a ruler will come out! My past go/no go experience with gas pressure cylinders of this kind has been to put one end on the floor and push with my body weight on the other. If they collapse at all they are no-go, if they don't they will probably work for a bit longer. Not very scientific! And it will of course only hold true for relatively light weight hoods. Do you know the actual weight of the door at the strut attachement point, with and without a properly adjusted torsion spring? Reason for my question: It should be fairly easy to determine if the torsion spring is at fault by attaching a push/pull spring scale to that point, although I think the weight/moment may be prohibitively high. My "D to be" has the droopy door syndrome. I want to buy genuine D replacements if necessary but I question if it is advisable to do so if the new ones are close to 20 years old? PJ Grady advertises a direct replacement, beefier and made to their specifications and that seems to be a smarter way to go. The present (past?) owner of my "D to be" indicated that a former member of the DMC club here in Minnesota had made a torsion bar tool, however, I do not have his name yet. (I helped a female friend some time ago to readjust her garage door torsion springs and that experience left me with a healty respect for the latent power in torsion bars, if you don't know EXACTLY what to do!) Roger